The present invention relates to fluid application devices and methods of using such devices.
Many people, including doctors and nurses require applicators for applying fluids such as, for example, topical skin adhesives. Various adhesive materials including cyanoacrylates can be used for closing or protecting wounds to the skin caused by trauma or surgery.
Emergency rooms, surgical suites, and many other health care settings find that topical skin adhesives are a safe and effective way to close wounds and prevent infection. Use of skin adhesives can also help reduce the pain and the fear that may accompany stitching the wound closed.
The original cyanoacrylate adhesives were discovered in 1942 in a search for materials to make clear plastic gun sights for the war. However, cyanoacrylates were quickly rejected by researchers because they stuck to everything. In 1951, cyanoacrylates were rediscovered by Eastman Kodak researchers, who recognized their true commercial potential.
The idea of using “super glue” to close wounds has been popular since the Vietnam War, when it was reportedly used in battlefield triage to raise the survival rate of American soldiers. Cyanoacrylate adhesives were reportedly used in veterinary use for mending bone, hide, and tortoise shell by about the early 1970s. Butyl cyanoacrylate has been used medically since the 1970s, but, due to its potential to irritate the skin, the U.S. Food and Drug Administration (FDA) did not approve its use as a medical adhesive until 1998.
Research has demonstrated the use of cyanoacrylate in wound closure as being safer than traditional suturing. Adhesives have demonstrated better performance in the time required to close a wound, incidence of infection, and cosmetic appearance.
This adhesive would closure technology as grown into a multi-million dollar business and is now widely accepted by the FDA and the worldwide medical community.
While standard “superglue” is typically ethyl cyanoacrylate (ECA), many custom formulations have come to be used for specific applications. Variations on N-butyl-cyanoacrylate are used for medical applications.
For example, Dermabond® is a Johnson and Johnson product that was first released in January 1998. It was the first surgical skin adhesive approved in the United States. Dermabond® has a purple tint that allows the health care professional to see where it is applied. It comes in a single-use applicator. According to Ethicon, a division of Johnson and Johnson, Dermabond® is recommended for facial wounds and surgeries because it does not leave scarring like sutures.
LiquiBand® Surgical skin adhesive was first marketed in the United Kingdom, and became available in the United States in 2009. Liquiband® comes in single-use containers. Liquiband® comes in seven different types of applicators. Each applicator is designed for a specific set of use circumstances and conditions. These include applicators for use in general surgery, laparoscopic surgeries, lacerations and minor wounds.
Histoacryl® topical skin adhesive is marketed by Aesculap. Their marketing material claim that it bonds in seconds. Histoacryl® comes in a clear or blue tint. Hystoacryl® is available in single use applicators.
According to Tissue Seal's website, Histoacryl does not contain stabilizers, and thus is stronger and needs fewer applications than similar products. The manufacturer also says that this difference keeps the applicators from clogging or drying out. The formula dries when it comes into contact with water or water-containing tissues like skin. Hystoacryl® was created and first marketed in Germany in 1968.
Indermil® tissue adhesive was approved in September 2002 for use in closing incisions and lacerations. The product is recommended for use in closing laparoscopic incisions. Indermil® is marketed by United States in single-use applicators.
Nexaband® is a veterinarian grade of Dermabond®. It is used in veterinarian clinics to close wounds on cats and dogs. Nexaband® is colorless and recommended specifically for cat declawing procedures. It is marketed by Abbott Animal Health and is not appropriate for use on people.
Applicators for the application of fluid, and in particular, adhesives to wound, require ergonomic designs that are easy to operate. It is advantageous for such applicators to include indicia for quick identification of a new applicator, rather than a used applicator.
The use of fluid or adhesive applicators allows a user, such as a surgeon or other medical professional, to control the application of fluid to a wound. It is desirable to allow the user to apply coating of desired thicknesses, widths, and lengths to a wound or other area that requires treatment.
Non-compliance with a prescribed regimen of treatment can result wound dehiscence, a surgical complication in which a wound breaks open along surgical suture, infection, additional surgery, pain and suffering for the patient, and unnecessary health care costs.
Known applicators include configurations in which a glass ampule is cracked by the hand action of a user to release a fluid. In some applicators, the fluid is contained in an aluminum foil tube. Other applicators can include a process in which a glass ampule is cracked using a gull wing hammer to release fluid or where a sponge is used to contain and express a fluid.
Known applicators have severe limitations. One such limitation is the inability of a user to express fluid, an adhesive for example, onto a wound in a precise and controlled manner. Another such limitation is the inability of a user to readily determine that the device has been used and needs to be replaced.
There are numerous other limitations of the existing technology which will become apparent with respect to the present disclosure. For example, aluminum foil applicators do not allow a user to see how much adhesive is remaining in the applicator, thus creating the potential risk of a surgeon running out of adhesive before the wound is completely closed.
“Single body” applicators designs are limited in that the applicators are pressurized when filling, thus when the tip is removed, the pressure inside the applicator may cause fluid to leak out or cause the user to apply more adhesive than intended (i.e. because pressure inside forces the fluid out of the applicator tip). Further limitations of some applicator designs include having to remove a tip to open the applicator in a sterile operating room environment. As such, the tip needs to be tracked and inventoried to ensure it has not been left in the patient, potentially causing life threatening complications. In addition, a narrow tip only allows for a “spot wielding” application technique which is time consuming and inefficient. Furthermore, with narrow tips, there is a risk that fluids, such as wound sealing adhesives, may enter the wound inadvertently.
Further applicator design limitations include the crushing of a glass ampule to activate and release an adhesive formulation. Such crushing of a glass ampule may cause shards of glass to penetrate a protective covering, if any, thereby jabbing the user's had, such as a surgeon or a doctor, with glass. While some designs have taken steps to limit glass shard penetration, this risk has not been eliminated. For example, for the last twelve years, hospitals have reported glass shard penetrations that have caused damage to surgeon's hands to the FDA Manufacturer and User Facility Device Experience (MAUDE) for adverse event reporting.
In addition, the ability to easily express and control the application of fluid with the aforementioned devices is difficult since the user, such as a surgeon or doctor, needs to control the expression of adhesive through multiple layers of a protective cover and the crushed ampule.
Some known applicator designs require a tab to be folded back to activate the applicator so that a fluid formulation can be released. Such designs are limited in that they require that the applicator tip, which can be a foam tip, come in contact with the wound. The FDA warns against such contacts. In addition, when an applicator having a foam tip comes in contact with body fluids, such fluids can be comingled with the applicator fluid, thus cause performance degradation. In some designs, the edges created by folding back a tab are sharp and have been known to cut or scrape patients or users of such applicators.
As detailed below, the present invention solves these and other difficult problems in a novel manner by improving the overall ease of compliance with a wound sealing protocols. For example, the instant invention is more efficient because a fresh new unit is easily identified for each application and the expression of fluid, such as adhesive, can be easily and carefully controlled by a user. The instant invention also eliminates the possibility that a user is cut by glass shards from an ampule.
Fluid applicators comprising novel multifunctional cutters and channels for opening fluid containing ampules, and expressing fluids, are disclosed herein.